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Compression Test results...What do you think?

  • Thread starter Thread starter joedokes28
  • Start date Start date Oct 6, 2008

joedokes28

Member
Jan 9, 2003
104
1
18
Photown, Az
Oct 6, 2008
#1
  • Oct 6, 2008
  • #1
I've been trying to get my stock 2v 289 running good again after many, many years of neglect. My goal here is 1, reliability and 2, decent performance.

While at the mechanic, we pulled the plugs and most of them were oiled bad. I had the shop do a compression test and here are the results:

1) 145
2) 160
3) 160
4) 165
5) 150
6) 170
7) 160
8) 150

The engine was rebuilt in 1982 to stock specs with hardened seats in the stock heads. Aside from this, I don't have much other info. I plan on doing an edelbrock 1450 carb and a performer rpm or stealth intake as the stock 2v is shot and in need of a major rebuild. I'm going to use the edelbrock carb as I already have it. The only other mods are hooker long tubes and full exhaust.

Just curious if this motor is still in good shape or should I cut my losses and start over?
 
1

10secgoal

Active Member
Dec 1, 2003
2,801
3
49
San Diego
Oct 7, 2008
#2
  • Oct 7, 2008
  • #2
It's horrible. I've seen worse. But squirt oil into the cylinders and try it again. that will tell you if it's a head or ring problem. If it's not smoking, I'd run it if you just want to put around.
 

joedokes28

Member
Jan 9, 2003
104
1
18
Photown, Az
Oct 7, 2008
#3
  • Oct 7, 2008
  • #3
I know the compression test was done dry. What would good numbers be for a stock 289?

It doesn't smoke and seems to run OK. I know the stock 2V 289 was no monster when they were brand new. If it's reliable for another year or so so I can finish the rest of the car, I'll be happy.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Oct 7, 2008
#4
  • Oct 7, 2008
  • #4
joedokes28 said:
I've been trying to get my stock 2v 289 running good again after many, many years of neglect. My goal here is 1, reliability and 2, decent performance.

While at the mechanic, we pulled the plugs and most of them were oiled bad. I had the shop do a compression test and here are the results:

1) 145
2) 160
3) 160
4) 165
5) 150
6) 170
7) 160
8) 150

The engine was rebuilt in 1982 to stock specs with hardened seats in the stock heads. Aside from this, I don't have much other info. I plan on doing an edelbrock 1450 carb and a performer rpm or stealth intake as the stock 2v is shot and in need of a major rebuild. I'm going to use the edelbrock carb as I already have it. The only other mods are hooker long tubes and full exhaust.

Just curious if this motor is still in good shape or should I cut my losses and start over?
Click to expand...


Those don't seem too bad. Generally if they're withing 10% of each other they're okay, if you take the average to be 160 (just eyeballing it that seems like ad ecent guess), then they're all within 10% of that.

Wouldn't worry about it if it isn't smoking.
 

Decurion

Member
Sep 28, 2006
353
0
16
Livonia, MI
Oct 7, 2008
#5
  • Oct 7, 2008
  • #5
SadbutTrue said:
Wouldn't worry about it if it isn't smoking.
Click to expand...

+1. While youre monkeying aroung with it, stick in a mild cam. A stock HO cam and a set of retrofit roller lifters from Crower would work nice and not break the bank, as stock cams can usually be had for free or darn close, and the lifters are about $220. Youll most likely need to upgrade the valve springs too, but that should make a nice difference without spending a ton of money or time. I think the stock 2v cams are real wheezers.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Oct 8, 2008
#6
  • Oct 8, 2008
  • #6
cylinders one and eight are a bit low, but acceptable. as long as you dont have any oil burning it is fine.
 

CraigMBA

New Member
Mar 24, 2007
783
1
0
Orange, CA
Oct 8, 2008
#7
  • Oct 8, 2008
  • #7
If you're going to stuff a cam inside a 20 year old engine with abnormally low compression, I have just one question.............

Why?

Don't touch it and drive it around or go through it.
 

joedokes28

Member
Jan 9, 2003
104
1
18
Photown, Az
Oct 8, 2008
#8
  • Oct 8, 2008
  • #8
CraigMBA said:
If you're going to stuff a cam inside a 20 year old engine with abnormally low compression, I have just one question.............

Why?

Don't touch it and drive it around or go through it.
Click to expand...

I agree. Don't want to spend much money on this motor as all.

Maybe someone will loan me a plate NO2 system so I can send this motor out with a BANG!
 

joedokes28

Member
Jan 9, 2003
104
1
18
Photown, Az
Oct 8, 2008
#9
  • Oct 8, 2008
  • #9
Double Post
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Oct 8, 2008
#10
  • Oct 8, 2008
  • #10
Test doesn't look that good, but I wouldn't call it "horrible".
 
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